Serah Farron [sɛrə] is a supporting character in Final Fantasy XIII and the main protagonist in Final Fantasy XIII-2. She is Lightning's younger sister by three years, and Snow Villiers's fiancée. Lightning accuses Snow of failing to protect Serah and does not initially approve of their relationship.
Snow Villiers
Snow Villiers is a playable character in Final Fantasy XIII and appears as a guest character in Final Fantasy XIII-2. He is a strong character and is capable of running at full speed while carrying a person, stepping on metal and easily bending it. Snow is determined to save his fiancée, Serah Farron, from her fate as a Pulse l'Cie, and everyone in Cocoon.
Noel Kreiss
Noel Kreiss is a playable character and the male protagonist in Final Fantasy XIII-2. He is the last remaining human from 700 years in the future, and has traveled into the past hoping to change that fate. After meeting Lightning by chance, he saves Serah Farron from monsters and accompanies her on her quest to find her sister.
Lightning
In Final Fantasy XIII, she tries to save her younger sister,Serah, only to be turned into a l'Cie like her. She fights to survive and see Serah come out of Crystal stasis. In Final Fantasy XIII-2, Lightning is now serving as a knight protecting the Goddess Etro in Valhalla from her fated rival, Caius Ballad.
Mog
In battle, Mog transforms into Serah Farron's signature Starseeker bowsword weapon. Mog also operates the new Mog Clock, which effects the status of enemies and the party depending on when the player strikes the enemies to initiate battle after they appear on the field.